204 CRUSTACEANS. 



neither of them strictly resembling either the Cancer or the Astacus. 

 The upper part is crustaceous, being invested by a shell, the under part 

 bare, soft, and void of segments, quite of fleshy consistence. Plate LIII. 

 fig. 1 ; LIV., both as in their shell ; Plate LIII. fig. 6 ; LIV. fig. 1. two 

 specimens, both without the shell. 



Two eyes in front are sustained on peduncles : rising within the roots 

 of these are two shorter forked antennae, besides two very long and slender 

 antennae, whose structure resembles that of a lobster, while in form 

 the internal antennae may be compared to those of the crab. 



Nominally, there are ten limbs, which, in the first place, exhibit a 

 great disparity between the size of the two claws. The first and second 

 pair of legs are long and strong ; the third and fourth short and abor- 

 tive. A projection crosses the extremity of the tail. 



Total length of the adult, six inches. 



Among the various shades and variegations of colours of different 

 specimens, red predominates. 



In some it is vivid almost throughout. The limbs of smaller sub- 

 jects are fine marbled, like tortoiseshell. 



Though, to shew the form and proportions, the claws be represented 

 here, they are, in fact, generally folded under the animal. 



This species feeds readily on animal substances. One claw holds 

 the shell of a bivalve, while the other picks out the contents. 



It is very lively, and very voracious. Several specimens may be 

 kept together with indemnity, for the nature of the hermit crab is paci- 

 fic. With strict attention to the purity of its element, a subject may be 

 preserved for a considerable time. 



This species is well adapted for experiment and observation. 



The process of exuviation is always interesting, because a new crea- 

 tion seems to attend it. But it is here somewhat different from that 

 above described, in partaking of another nature. One-half of the inte- 

 guments, namely, the upper portion or crustaceous parts, are all that 

 separates, for there is no possible exuviation by changing the skin of the 

 lower or fleshy portion. 



If it does separate, the change is insensible. The former comes off 



